CVE-2026-20838

This kernel flaw hits Windows Server 2022 and the Server Core builds of both Server 2022 and Server 2025, and predictive scoring puts a 73 percent chance of exploitation attempts, unusually high for a bug that has not yet been added to CISA's known-exploited list. A kernel information disclosure bug like this typically leaks memory contents an attacker can use to defeat ASLR before a separate code execution exploit. No active exploitation or ransomware use has been confirmed yet, but the exploit-probability score says treat it as a when, not an if.

Do this: Prioritize patching all Windows Server 2022 and Server 2025 Server Core hosts for this CVE before the next maintenance window.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.